Homopolymerization of acrylate or methacrylate endblocked polydiorganosiloxanes
Method for homopolymerization of polyorganosiloxane macromonomers having acryloxy or methacryloxy groups. A miniemulsion of a methacryloxy functional polydimethylsiloxane macromonomer was prepared by mixing the macromonomer with a surfactant(s), and subjecting it to a high shear device. The macromonomer was polymerized in the miniemulsion by using a free radical initiator at high temperature. The amount of unreacted macromonomer is very low.
Latest Dow Corning Corporation Patents:
- DUAL CURE ADHESIVE COMPOSITION AND METHODS FOR ITS PREPARATION AND USE
- DUAL CURE ADHESIVE COMPOSITION AND METHODS FOR ITS PREPARATION AND USE
- Catalysis of dehydrocoupling reactions between amines and silanes
- Silicone acrylate compositions and methods of preparing the same
- Curable composition, method of preparing cured article, and cured article formed thereby
Claims
1. A method of making an emulsion containing a homopolymer of a polyorganosiloxane having acryloxy or methacryloxy groups, comprising heating and shearing a reaction mixture formed by combining (i) water; (ii) an anionic surfactant, a cationic surfactant, a nonionic surfactant, or a combination thereof; (iii) a cosurfactant which is a hydrophobic solvent, or a compound having low water solubility, selected from the group consisting of fatty alcohols, n-alkanes, and halogen substituted n-alkanes; (iv) a mono-acryloxyalkyl terminated polydiorganosiloxane macromonomer (I) or a mono-methacryloxyalkyl terminated polydiorganosiloxane macromonomer (II) having the formula ##STR8## where R in each formula is a divalent hydrocarbon radical with 1-6 carbon atoms; R2 in each formula is the hydrogen atom, a C.sub.1-8 alkyl radical, a haloalkyl radical, or an aryl radical; and z in each formula is 1-1,000; and (v) a free radical initiator.
2. A method according to claim 1 in which the cosurfactant is a compound selected from the group consisting of cetyl alcohol, n-hexadecane, and 1-chlorodecane.
3. A method according to claim 1 in which the free radical initiator is an azo initiator.
4. A method according to claim 3 in which the free radical azo initiator is a compound having the formula ##STR9## where R' is an alkyl radical, and Q is a carboxylic acid residue.
5. A method according to claim 4 in which the free radical initiator is 2,2'-azobisisobutyronitrile or 4,4'-azo-4-cyanopentanoic acid.
6. A method according to claim 1 in which the homopolymer of the polyorganosiloxane having acryloxy or methacryloxy groups has the formula ##STR10## where R1 in each formula is the polydiorganosiloxane moiety --(OSiR2.sub.2).sub.z OSiR2.sub.3; R2 in each formula is the hydrogen atom, a C.sub.1-8 alkyl radical, a haloalkyl radical, or an aryl radical; R in each formula is a divalent hydrocarbon radical with 1-6 carbon atoms; x in each formula is 2-5000; and z in each formula is 1-1,000.
7. A method according to claim 6 in which the homopolymer has the formula ##STR11## where R2 in each formula is the hydrogen atom, a C.sub.1-8 alkyl radical, a haloalkyl radical, or an aryl radical; x in each formula is 2-5000; y in each formula is 1-6; and z in each formula is 1-1,000.
8. An emulsion containing a homopolymer of a polyorganosiloxane having acryloxy or methacryloxy groups made according to the method defined in claim 1.
4499398 | February 12, 1985 | Gravier et al. |
4533254 | August 6, 1985 | Cooj |
4620878 | November 4, 1986 | Gee |
4918123 | April 17, 1990 | Yang et al. |
4962165 | October 9, 1990 | Bortnick |
5234773 | August 10, 1993 | Biale |
5502105 | March 26, 1996 | Revis |
5504149 | April 2, 1996 | Kosal |
5561188 | October 1, 1996 | Liles et al. |
5563214 | October 8, 1996 | Share et al. |
5594067 | January 14, 1997 | Doi et al. |
- Journal of Applied Polymer Science, vol. 43, 1059-1066, (1991). No Author No Title. Polymer Processing, 44 (11), 490-497, (1995). No Author No Title.
Type: Grant
Filed: Jan 3, 1997
Date of Patent: Nov 24, 1998
Assignee: Dow Corning Corporation (Midland, MI)
Inventors: Gerald Alphonse Gornowicz (Midland, MI), Linda Denise Kennan (Midland, MI), Anil Kumar Saxena (Midland, MI), Arthur James Tselepis (Midland, MI)
Primary Examiner: James C. Housel
Assistant Examiner: Rodney P. Swartz
Attorney: James L. DeCesare
Application Number: 8/779,852
International Classification: C08F28300; C08F 2608; C08J 554;